


That Awkward Moment When You Get Stuck In A Cell And Go Into Heat

by TellTaleKael



Series: Undertale Kinktober 2019 [2]
Category: Undertale (Video Game)
Genre: Age Difference, Apple Is My Horrorlust Ship Child, Apple Is The Skeleton Monster Equivalent Of 19-20 But Cross Calls Him Kid, But For This One, Coaching, Cross As Dream’s Guardian, Good Guy Cross, Intercrural Sex, Kinktober 2019, Listen This Is A Cliche Storm But I Love My Boy Apple And Sometimes He Needs Some Dick, M/M, Mating Cycles/In Heat, More On Him Later, Slight Dom/Sub, Smut, soft dom
Language: English
Status: Completed
Published: 2019-10-02
Updated: 2019-10-02
Packaged: 2020-11-15 11:49:43
Rating: Explicit
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 1
Words: 3,391
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/20865737
Author URL: https://archiveofourown.org/users/TellTaleKael/pseuds/TellTaleKael
Summary: Undertale Kinktober 2019Day 2: Soft Dom/Coaching, Intercrural Sex | Pairing: Cross/AppleApple really should have listened to his Dad. Not doing so landed him in a dark, dank, dirty cell, with an injured, stoic Cross for a cell mate. It really couldn’t get any worse....could it?





	That Awkward Moment When You Get Stuck In A Cell And Go Into Heat

**Author's Note:**

> If you want to know more about Apple, check the end notes for some fun facts. I plan on using him more in the future, maybe even trying to make some comics about him.

Apple really should have listened to his Dad. He thumped his skull against the stone wall of the cell with a groan. He was trapped, the cell warded with magic to prevent teleportation, or any attacks that could bust him out of there. Nightmare’s personal cells, somewhere deep within the bowels of his castle.

He and his Dad had been visiting Ink and the other Star Sanses when Nightmare had attacked, using the opening in the doodlesphere that allowed the two of them in to sneak in and launch an offensive attack. Though caught off-guard, the Star Sanses would have probably been fine on their own, but Apple’s Dad, Lust, never turned his back on a monster in need. He’d told Apple to run, to go back home through the portal, but Apple had stayed to try and help with the fight.

That had gone sooooo well, hadn’t it?

Apple thumped his head against the wall again. It had been Killer who had snatched him up, recognizing the scar on his head. The one that matched the injury of his father- Horror. Apple wasn’t sure if they planned on using him to try and get at Horror or what, but it wouldn’t work. He hadn’t seen his father since he had been a babybones.

As much fun as abusing his skull against the rough rock was, he stopped hitting himself against it and plodded over to the bare mattress on the floor in the corner. Maybe if he slept, he’d wake up to someone coming to help him? He flopped down on the mattress and closed his sockets, willing time to pass.

——

When he woke, it was to the disorienting shouts of nearby monsters, and an unbearable itching where his body touched the questionable mattress. Apple sat up, rubbing at a socket sleepily. Then it hit him; shouting. Monsters nearby. Maybe his Dad had come for him! He hopped up and bounded over to the cell door, pressing his skull to the bars and trying to see as far down the corridor as he could.

His grin faded when Killer came into view, manic smile stretched across his stained skull. He was dragging something.

“Get outta the way before I slice ya!” Killer barked, and Apple scurried to obey, pressing himself against the far wall. He didn’t want to test the limits of Killer’s patience, nor his rationality. Even if he rushed the door and escaped, he was still lost in Nightmare’s castle, perhaps even surrounded by his crew just waiting to pounce.

The door clanged open, and Killer hurled in a mass that slumped against the floor where it landed. Apple waited until the maniac was gone, before rushing forward. It was Cross. Former servant of Nightmare turned guardian for Dream. His sockets were closed, body battered, but he groaned when Apple flipped him over, so he was alive at least. There was a nasty gash on his chest, and Apple hesitated. He wasn’t the best healer, not like his Dad. His magic was unstable at times, and he risked overloading the other with too much magic all at once. But when he checked Cross’ HP, it was dangerously low. With a deep breath, he called his magic up. Oh, right. The wards stifled his magic. But that actually worked in his favor, preventing his magic from spiking suddenly and harming Cross.

Placing his hand against the older skeleton’s chest, he began to filter magic into the wound. The wards kept his magic from spiking, and slowly but surely the gash began to close, and Cross’ HP began to rise. Apple ignored the burn in his own chest and abdomen, refusing to stop until... there! The wound sealed over, and he cut his magic off. He had done it!

Standing made the room spin, and he wobbled slightly. Healing was hard, intricate work. The mattress, as questionable as it was, called his name. But Cross was still slumped on the cold stone floor. Apple leaned down to loop his arms under Cross’, dragging him over to push him onto the mattress. The effort made him woozy, and he fell down beside Cross on the scant cushion. Right, he would just close his sockets for a moment...

——

Burning.

Itching.

Apple’s body tensed before relaxing. Something shook him. He blearily opened his sockets once more, only to come face-to-face with Cross, who looked extremely uncomfortable, perhaps because Apple had basically become and octopus in his sleep and wrapped his arms and legs around the older skeleton like he was a teddy bear. Apple made a noise of surprise and pushed away from him, flopping off of the mattress and onto the floor. He laid there for a moment, groaning. Maybe he could go back to sleep and pretend he hadn’t cuddled Cross in his sleep.

But alas, it wasn’t to be. He heard Cross shift, climbing off of the mattress and coming to stand by Apple’s sad, slumped form on the floor. “Hey, you okay?” Apple groaned and lifted a hand to shoot a thumbs up. He could hear Cross’ footsteps pace across the cell, and then back again. “Place is warded and locked up tight.”

Apple rolled over with a groan, body itching and sore. “Yeah. I already looked around, didn’t find anything. They took my weapon, yours too.” Without the massive blade, Cross almost looked... small. Though he was one of the taller Sanses in reality, he just looked much... less, without his blade. Apple reluctantly sat up, not even wanting to think about the grimy state of the floor beneath him. He looked up, and found Cross’ eye on his skull, specifically the left side, where his scar was.

“You’re Horror’s kid, right?”

Apple frowned. “No. I’m Lust’s son,” he corrected, a little snappily. Cross didn’t react to his sharp tone.

“Were you the one who healed me?”

Taken aback by the sudden change in topic, Apple nodded. “Uh, yeah. It looked pretty bad, and you weren’t waking up.” He didn’t know Cross personally, but that didn’t mean he would be okay with sitting by and watching him dust.

“Thank you.”

“I wasn’t going to watch you die if I could help it.” He wasn’t even sure if Cross would have died. The other monster had an impressive amount of HP, and his stats were elevated as well. He might have been okay.

Cross didn’t reply, just nodded. Apple stood, suddenly filled with a nervous energy. Being thrown into a damp cell with a thin mattress to rest on wasn’t good for the body, it turned out. He paced around the small space, trying to calm himself and feel less jittery. Cross watched him, face impassive. Sweat began to gather on Apple’s skull and spine. Maybe he had been too hasty in his judgement of the situation? Would the Star Sanses be able to find him in the middle of Nightmare’s territory? Was this what a panic attack felt like?

“Is it hot in here?” he asked Cross. The older skeleton shot him an incredulous look. His bones prickled. It almost felt like...

“You’re going into heat,” Cross said matter-of-factly.

——

“I can’t take it,” Apple growled, sitting up from where he was sprawled out on the mattress. His hands flew to the clasps of his overalls, frantically undoing them. Cross looked at him with a cocked browbone from across the cell. He had pressed himself against the far wall about the time that the scent of pomegranates began to fill the air, courtesy of Apple’s ill-timed and unfair biology. Apple managed to get the clasps done, and he stood, shimmying out of the overall shorts, kicking them aside. Cross made a noise, but Apple ignored it, lying back on the mattress in only his long sleeved shirt.

“I’ve got to get some kind of relief. Just, don’t look. Or do, I really don’t care,” he said, spreading his knees and summoning the lower half of his body. With the heat already sparking magic across his bones, it was easy to form the ecto flesh, a light maroon color that glowed in the dim light of the cell. He’d instinctively chosen a cock, finding it easier to get off solo that way. The first touch of his hand around the heated flesh made him groan unabashedly.

There was a sharp intake of breath from across the cell, but when Apple craned his head to look, Cross was diligently looking at the cell door, and not at Apple.... though there was a dusting of purple across his cheeks. As awkward as it was, Apple just hoped that Cross understood, and wouldn’t be weird about it. He let his skull flop back against the mattress and chased the first release of his heat with his hand, trying to stay quiet.

——

Sweat coated his bones, dripping, unable to dry even in the cool air of the cell. Apple gave a frustrated groan, twisting his fingers inside of himself sharply, trying to find his sweet spot. He’d come three times already by then, and even managed a little bit of sleep, but his heat just was not giving up. Pomegranate and dark chocolate scents filled every breath, and he had given up hope for his shirt, ripping it off and leaving him bare. He really wished someone would come find them already, because he could practically feel Cross looking at him, but he was too far gone to care about propriety or even how desperate and pathetic he must look.

Also it was really beginning to hurt, and he was thirsty as hell.

Slipping his fingers out of the pussy he had swapped out for after his second orgasm, Apple slumped down with another frustrated, whining groan. He closed his sockets, trying to will himself back to sleep. It was futile and he knew it. Instead, he rolled over and intentionally looked at Cross for the first time since he had started touching himself.

Purple stained the older skeleton’s skull, a deep flush that didn’t look like it was going to go away soon. He panted slightly, chest visibly rising and falling under his ruined clothing. There was a glow coming from within, and Apple was sure that, were Cross facing him, he would see a bulge in the dark pants the other wore.

Having grown up in Underlust, Apple had been taught that heats, and the natural reactions to their influences, were perfectly normal. They were a part of life as a monster, and nothing that he was ashamed of. He found it flattering when his heat scent affected another, when they found his natural pheromones attractive. He certainly didn’t think any less of the normally-stoic Cross for reacting to his heat. Unlike what some monsters from other universes seemed to think, heats were not a thing that could strip one of all their rational thoughts. They were no excuse for going after someone who didn’t want you back.

But that meant you could have a conversation, even deep in the midst of a heat. It was for that reason that he cleared he throat to catch Cross’ attention.

“Listen, Cross, uh... I know we’re both pretty uncomfortable now, but we really don’t know how long it will take for us to get out of here.” He sat up, ignoring the cramping in his abdomen. “You can say no of course, but if you wanted to... we could do a little something to make the both of us less comfortable, you know?”

Cross stared at him, long enough that Apple began to worry he had said something wrong or offended the older skeleton in some way. He opened his mouth to backtrack, to apologize, but Cross beat him to the punch.

“It wouldn’t mean anything.”

Apple shook his head. “No, of course not! I barely even know you, I definitely am not going to attach anything emotional to this. And I’m not going to be crushed if you say no. I just thought I’d bring it up and see if you were interested.”

Cross hesitated for only a moment before nodding. Relief made Apple’s knees go weak, but he hopped up. “Alright, if you wanna-“

“Sit down,” Cross cut him off with. Apple, without even thinking, did as he was told. Cross moved across the room, coming at a stop in front of Apple. He began to strip himself out of his clothes, piece by piece. Like Apple, he had only summoned his body up to his abdomen, but even with that it was easy to see that the flesh was sculpted with muscle. Cross had probably the strongest ecto body that Apple had seen, corded thighs and sharp hips leading up to a defined abdomen. His cock hung thick and heavy between his thighs, and just the sight of it made Apple’s inner muscles clench.

Cross stood still, waiting until Apple had looked his fill. Despite the already heavy arousal he displayed, he was gentle as he reached out to cup Apple’s skull. He pressed a skeleton kiss to Apple’s forehead with a quiet clack. “Lie back,” he commanded quietly. Apple moved to do so. It shouldn’t have been a surprise that Cross was authoritative in bed; what little Apple knew about him had shown that he was a very serious, strong individual. Apple certainly wasn’t against taking directions, at least in a situation like this.

Instead of crawling on top of Apple, as expected, Cross slipped beside him, directing Apple to roll over on his side and curling up behind him. A heavy hand settled low on his stomach, rubbing soft circles. It wasn’t even anything special, but the touch made Apple shiver. Some of the desperation faded from him, the heat falling to a background burn instead of a hot fire. Cross’ breath puffed against Apple’s neck when he spoke.

“Can you change your form?” Apple nodded. “Then I would like it if you brought that nice cock back for me.” Almost instantly, Apple did, and Cross chuckled at his eagerness. “Good boy.”

Whew, the older skeleton was hitting all of Apple’s favorite kinks. The hand that rubbed circles on his stomach slipped lower, knuckles teasing along the side of his cock. It made him gasp, even just the light hint of contact felt so much better than his own hand. He pressed back against Cross, rubbing against the hard bulge between those strong legs.

“Are you going to get a move on? I know we’re trapped here, but I don’t actually have all day.”

Cross twisted his hand, slipping the tip of his thumb into the slit at the top of Apple’s cock. A whimper left him, unbidden, and he could feel the smirk the stretched across Cross’ face. “I’m sorry, what was that?” Cross asked mildly. Apple swallowed thickly.

“P-please, can you touch me?”

“I am.” Now Cross was just being mean. Apple shifted, a bead of magic rushing to the tip of his cock to coat Cross’ phalange.

“No, I mean...” Apple took a deep breath. “My heat is really starting to hurt. Can we please do something about it?”

Cross nodded. “Now’s not really the time to tease,” he admitted, almost regretfully. He moved both hands down to part Apple’s legs. A wave of panic hit him, and he tried to close his legs.

“W-wait, I’m not stretched out,” Apple warned, but Cross merely held his legs open and moved closer. His cock settled on Apple’s thigh.

“You don’t need to be.” Cross lowered Apple’s leg, bringing his thighs together. They closed around the older skeleton’s cock, creating a warm channel around it. Slowly, Cross began to roll his hips. The movement allowed him to fuck Apple’s thighs, and each thrust slid against Apple’s cock as well, sending sparks of pleasure up his spine.

“Oh...” Apple breathed, catching on to what Cross was doing. He tightened his legs, making Cross’ hips stutter before picking up the pace. The magic from Apple’s previous release and what leaked from the tip of Cross’ cock slicked up his thighs, easing the way and allowing them both to rock against one another smoothly. It wasn’t quite what Apple had in mind when he’d made his proposition, but he couldn’t deny that it felt good. Cross gripped at his hips tightly, panting out praises, directions like, “Tighter,” and “Twist your hips,” that Apple followed. Soon, their combined moans filled the cell, and a pang of pride hit Apple when he realized that they weren’t even having penetrative sex, but he still managed to pull those noises out of the older skeleton.

As wound up as they both were- Apple from his heat, and Cross from both the scent and sight of Apple getting off earlier- it didn’t take long before the pace grew sloppy and desperate. Cross leaked so much magic that Apple’s thighs looked stained purple, and his phalanges tightened on Apple’s flesh. Apple himself wasn’t any better, hips aching from the force with which he met each thrust. The burn of his heat was overpowered by the building pleasure, and he was the first to reach the peak, hands scrabbling for purchase against the old mattress as he came with a strangled groan. He did his best to keep his legs tight, trying to pull Cross over the edge with him. Finally, after a few more thrusts, Cross came with a low curse, spilling on Apple’s thighs, coating them thoroughly.

Apple drifted for a moment, pleasure and the satiation of his heat leaving him floating. When he came back, it was to Cross carefully cleaning him off with his torn shirt. When they were both as clean as they could get, Cross tossed the clothing aside and slipped back on the mattress, spooning up against Apple.

“How do you feel?” Cross asked after a moment. Apple smiled sleepily.

“Fantastic. That was just what I needed.” He yawned. “Thank you.”

Cross hummed and tucked his face against Apple’s shoulder. “Get some rest, kid. I’ll wake you if anything happens.”

Apple was asleep before the last word.

——

“Kid. Hey, kid.”

A hand shook Apple, and he reluctantly pried his sockets open. He turned his head to see Cross standing above him, back in all of his clothes sans (heh) his shirt. Apple reluctantly sat up, and Cross handed him his clothes.

“Better get dressed. We’re about to have company. Whether it’s Nightmare’s gang, or someone else, I figured you’d want to be dressed for it.”

Apple nodded and quickly struggled into his clothes, only once making a face at the magic crusted on his bones. A bath was the first thing he needed when he got out of there, for sure. At least his heat had quietened down. He would probably be good for the rest of the day, at least.

They both tensed when footsteps approached at a pace that suggested the owner of them was running full sprint. Apple let out a breath he hadn’t realized he had been holding when Dream rounded the corner, staff in hand.

“Cross! And Apple!” Dream cried out. “You’re both here! Good. We have to get you out. Stand back.”

Apple and Cross moved into the corner as far away from the door as possible. It was flung off of its hinges. Finally, they were free. Cross strode through the doorway, hand coming up to cup Dream’s face gently. They exchanged quiet words, but Apple didn’t even try to hear, because at that moment Lust came into view as well.

“Dad!” Apple threw himself at his Dad, who swept him up in a bone crushing hug.

“Don’t you ever to that to me again,” Lust said sternly, pulling back to look Apple over critically. Apple squeezed Lust’s hand.

“I’m okay Dad. Really.”

Lust broke into a softer smile. “You are,” he agreed.

“We need to leave,” Dream said. Lust let go of Apple and turned.

“Right. We need to give Ink and Blue the all clear.”

“I’ll take care of it,” Dream said. “You two get out of the castle and teleport away. Don’t worry about us.”

Lust nodded in affirmation and headed for the stairs that led back to the upper floors. Apple followed, glancing back only once. Cross met his eyes, inclined his head, and then he was out of sight.

**Author's Note:**

> Five Fun Facts about Apple:
> 
> 1\. Apple is a Horrorlust child, created by Ink for Lust.
> 
> 2\. Ink created Apple’s body and a soul container, and then Lust’s and Horror’s magic went into the container to form a soul. 
> 
> 3\. Currently in ‘canon’, Horror and Apple want nothing to do with one another.
> 
> 4\. Though Apple is part Underlust monster, he does not have the horrible heats Underlust monsters have. He does have a flexible ecto form and sex magic (that he’s still trying to figure out).
> 
> 5\. Apple is sometimes a lil bitch lmao.
> 
> If you’d like to know more about my weird little guy, stay tuned, because I plan to write more with him~! Also, at the time of posting this, he’s in my profile pic if you wanna see him. He has a little birthmark/scar on his head similar to the hole in Horror’s skull.


End file.
